In my experience, entry-level units like NAD, Parasound and Musical Fidelity sound painfully two dimensional and lifeless when compared to moderately-priced tube-based phono stages. In particular, I'm thinking about a $600
Wright WPP100C and a $650
EAR 834P, but these may be beyond your budget. All things considered, a good phono preamp can make a huge difference. Don't underestimate its importance.
A Jolida JD-9a would be a nice upgrade for $350 as Viridian suggests.
If you're handy with a soldering iron, and willing to build a kit, you can get top-notch performance on a shoe-string budget.
I was going to recommend the
Bottlehead Seduction for $279, but it doesn't have enough gain for your cartridge.
The
Juicy Music Tercel kit would be an excellent choice for $395.
Jim Hagerman's
Cornet2 kit is a giant killer for about $400-500. The instructions are easy to follow and Jim is extremely helpful. There's an active DIY group at Audio Circle and Audio Asylum if you need advice.
I encourage you to check out this forum:
please help me choose a new budget phono pre